Implementation of a multiple risk factor intervention trial for the prevention of coronary heart disease. Participate with other investigators leading to a controlled intervention study involving the screening of defined populations to identify men with an elevated risk for developing coronary heart disease and establishment of the intervention modaliti es for the reduction of cholesterol by diet, blood pressure reduction by anti-hypertensive drugs and reduction of smoking. Establish a Core staff for the undertaking of the intervention protocol with training of staff in the conduct of responsibilities. Establish necessary community relations with local physicians and population to be screened for planned recruitment of approximately 600 participants.